The present invention relates to a method and an apparatus for contact-free removal of dirt from various cylinders of printing machines.
International Application WO 89/01 412 discloses a system in which "blanket cylinders" are cleaned by spraying them with a mixture of water and a solvent. The particles of dirt which particularly consist of residues of printing ink from the inks transferred to the material being printed, of paper fibers of the material being printed, and of dust, are dissolved by the water/solvent mixture and are transferred in the press nip between two adjacent cylinders onto the material being printed as it passes through the press nip. This dirties the material being printed with the particles of dirt. In the subsequent dryer through which the web of material being printed then passes, the easily flammable solvent vapors, which evaporate from the material being printed, could cause an explosion or fire in the dryer if their concentration exceeds a maximum permissible value.
Furthermore, Federal Republic of Germany Application 30 05 469 A1 discloses a washing beam including means for washing the rubber blanket cylinders of a printing unit. The washing beam sprays water and/or solvent on the rubber blanket cylinder in order to soften and detach particles of dirt and then, by means of a wash cloth, wipes the dissolved particles of dirt off from the rubber blanket cylinder. The wash cloth is transported from a clean cloth roller to a dirty cloth roller, so that a clean section of wash cloth is always applied to the rubber blanket cylinder. The dirtied wash cloth must be frequently replaced. The washing beam undesirably requires a large amount of space, which affords difficulties since only a small amount of space is available between individual printing units of a printing machine.
There are also other objects, the cleaning of which requires a large amount of time and a large expense, including machine tools, metal articles from which rust is to be removed, household implements, and similar items. The invention is useful for them too.
European patent application publications EP 454 604, EP 451 304, EP 449 745 and DE 40 13 163, describe removal of (ablate) material from an article in order to change the shape of the article or to provide access through the outer layers of the article to its inner layers. In contrast to such machining and changing the surfaces of objects, no machining of an object is provided in the present invention. Instead, the object, and in particular its surface, is not changed. Furthermore, it is also known to provide layers of material to objects through the use of laser beams or to solder the layers by means of laser beams.